[libvirt] [PATCHv7 3/4] libvirt/qemu - check address confliction before addition.

[KAMEZAWA Hiroyuki]

>From 638341bdf3eaac824e36d265e134608279750049 Mon Sep 17 00:00:00 2001
From: KAMEZAWA Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com>
Date: Fri, 25 Mar 2011 17:10:58 +0900
Subject: [PATCHv7 3/4] libvirt/qemu - check address confliction before addition.

qemuDomainAttachDevicePersistent() calls qemuDomainAssignPCIAddresses()
and virDomainDefAddImplicitControllers() at the end of its call.

But PCI/Drive address confliction checks are
 PCI - confliction will be found but error report is not verbose.
 Drive - never done.

For example, you can add following (unusual) 2 devices without errors.

<disk type='file' device='disk'>
   <driver name='qemu' type='raw'/>
   <source file='/var/lib/libvirt/images/test3.img'/>
   <target dev="sdx" bus='scsi'/>
   <address type='drive' controller='0' bus='0' unit='0'/>
</disk>

<disk type='file' device='disk'>
   <driver name='qemu' type='raw'/>
   <source file='/var/lib/libvirt/images/test3.img'/>
   <target dev="sdy" bus='scsi'/>
   <address type='drive' controller='0' bus='0' unit='0'/>
</disk>

It's better to check drive address confliction before addition.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com>
---
 src/conf/domain_conf.c   |   59 ++++++++++++++++++++++++++++++++++++++++++++++
 src/conf/domain_conf.h   |    2 +
 src/libvirt_private.syms |    1 +
 src/qemu/qemu_driver.c   |    9 +++++++
 4 files changed, 71 insertions(+), 0 deletions(-)

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 3e3f342..4a54f62 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -1287,6 +1287,65 @@ void virDomainDefClearDeviceAliases(virDomainDefPtr def)
     virDomainDeviceInfoIterate(def, virDomainDeviceInfoClearAlias, NULL);
 }
 
+static int virDomainDeviceAddressMatch(virDomainDefPtr def ATTRIBUTE_UNUSED,
+                                       virDomainDeviceInfoPtr info,
+                                       void *opaque)
+{
+    virDomainDeviceInfoPtr checked = opaque;
+    /* skip to check confliction of alias */
+    if (info->type != checked->type)
+            return 0;
+    if (info->alias && checked->alias && strcmp(info->alias, checked->alias))
+            return -1;
+    if (!memcmp(&info->addr, &checked->addr, sizeof(info->addr)))
+            return -1;
+    return 0;
+}
+
+int virDomainDefFindDeviceAddressConflict(virDomainDefPtr def,
+                                          virDomainDeviceDefPtr dev)
+{
+    virDomainDeviceInfoPtr checked;
+
+    switch (dev->type) {
+    case VIR_DOMAIN_DEVICE_DISK:
+        checked = &dev->data.disk->info;
+        break;
+    case VIR_DOMAIN_DEVICE_FS:
+        checked = &dev->data.fs->info;
+        break;
+    case VIR_DOMAIN_DEVICE_NET:
+        checked = &dev->data.net->info;
+        break;
+    case VIR_DOMAIN_DEVICE_INPUT:
+        checked = &dev->data.input->info;
+        break;
+    case VIR_DOMAIN_DEVICE_SOUND:
+        checked = &dev->data.sound->info;
+        break;
+    case VIR_DOMAIN_DEVICE_VIDEO:
+        checked = &dev->data.video->info;
+        break;
+    case VIR_DOMAIN_DEVICE_HOSTDEV:
+        checked = &dev->data.hostdev->info;
+        break;
+    case VIR_DOMAIN_DEVICE_WATCHDOG:
+        checked = &dev->data.watchdog->info;
+        break;
+    case VIR_DOMAIN_DEVICE_CONTROLLER:
+        checked = &dev->data.controller->info;
+        break;
+    case VIR_DOMAIN_DEVICE_GRAPHICS: /* has no address info */
+        return 0;
+    default:
+        virDomainReportError(VIR_ERR_INTERNAL_ERROR,
+                             "%s", _("Unknown device type"));
+        return -1;
+    }
+    if (checked->type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE)
+        return 0;
+    return virDomainDeviceInfoIterate(def, virDomainDeviceAddressMatch, checked);
+}
 
 /* Generate a string representation of a device address
  * @param address Device address to stringify
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index b791714..53ccf32 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -1194,6 +1194,8 @@ int virDomainDeviceInfoIsSet(virDomainDeviceInfoPtr info);
 void virDomainDeviceInfoClear(virDomainDeviceInfoPtr info);
 void virDomainDefClearPCIAddresses(virDomainDefPtr def);
 void virDomainDefClearDeviceAliases(virDomainDefPtr def);
+int virDomainDefFindDeviceAddressConflict(virDomainDefPtr def,
+                                           virDomainDeviceDefPtr dev);
 
 typedef int (*virDomainDeviceInfoCallback)(virDomainDefPtr def,
                                            virDomainDeviceInfoPtr dev,
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 7459c40..ffdf9cf 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -220,6 +220,7 @@ virDomainCpuSetParse;
 virDomainDefAddImplicitControllers;
 virDomainDefClearDeviceAliases;
 virDomainDefClearPCIAddresses;
+virDomainDefFindDeviceAddressConflict;
 virDomainDefFormat;
 virDomainDefFree;
 virDomainDefParseFile;
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 4d3b416..e746576 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -4144,6 +4144,9 @@ cleanup:
     return ret;
 }
 
+/*
+ * Checking device's definition meets qemu's (and qemu drivre's) limitation.
+ */
 static int qemuDomainDeviceAddressFixup(virDomainDefPtr vmdef, bool pci)
 {
     if (!pci && virDomainDefAddImplicitControllers(vmdef))
@@ -4163,6 +4166,12 @@ static int qemuDomainAttachDevicePersistent(virDomainDefPtr vmdef,
     bool pci;
     int ret;
 
+    if (virDomainDefFindDeviceAddressConflict(vmdef, newdev)) {
+        qemuReportError(VIR_ERR_INVALID_ARG, "%s",
+                        _("the device address already in use"));
+        return -1;
+    }
+
     switch(newdev->type) {
     case VIR_DOMAIN_DEVICE_DISK:
         disk = newdev->data.disk;
-- 
1.7.4.1